Android architecture components, in collaboration with Amine Athmani

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2. Hi
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3. How can we make delicious
Indian dishes
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4. Android
Architecture Components
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5. Amine ATHMANI
GDG Algiers Co-manager
Azzeddine CHENINE
GDG Algiers Co-manager
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6. Android
Has Good Bones
Activities and Fragments
Content Providers
Services
Broadcast receiver
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7. The painful Activity
Lifecycle
Home button clicked
Back button clicked
App hoping
Screen rotation
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8. Everyday problems
Facing Android developers
App components lifecycle is not under control
Data stored in components is being lost
OS may kill your app at random
time
UI changes
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9. Is it really that complicated ?
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10. Principles
We must Keep in mind
Separation of concerns
Drive your UI from a model
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11. Meet MVC
Model-View-Controller
Model: the data layer, manages the business logic and handling network
or database API.
View: the UI layer , a visualisation of the data from the Model.
Controller: the logic layer, gets notified of the user’s behavior and
updates the Model as needed.
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12. Meet MVC
Model-View-Controller
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13. How Should
MVC Be applied in Android
Views
Model and Controller
Activities, Fragments
Android free classes
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14. perks and cons
Separation of concerns, testability and SRP
Complex dependencies, Lifecycle and UI changes
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15. Moving to MVP
Model-View-Presenter
Let’s reduce the dependencies
Make a presentation layer for data retrieved from the
model
Sign a contact between the view and the presenter
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16. Moving to MVP
Model-View-Presenter
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17. How the Presenter-View contract
Is made
Ipresnter
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18. How the Presenter-View contract
Is made
IView
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19. Land on MVVM
Model-View-Presenter
View: informs the ViewModel about the user’s actions.
View model: exposes streams of data relevant to the View.
Data Model: abstracts the data source.
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20. Land on MVVM
Model-View-Presenter
If the MVP pattern meant that the Presenter was telling the View directly
what to display, in MVVM, ViewModel exposes streams of events to
which the Views can bind to.
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21. Land on MVVM
Model-View-Presenter
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22. Not all heroes wear caps!
Android team is bringing MVVM to Android
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23. Android
Architecture Components library
RoomLive dataView model
Lifecycle aware
Component
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24. Android
Lifecycle aware components
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25. Fragments or Activities are
lifecycle owners
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26. Their lifecycle is observed by
A lifecycle observer
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27. Lifecycle owner
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28. Lifecycle observer
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29. Android
View Model and live Data
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36. ViewModel example
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37. View example
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38. Avoid reference to Views
In View Models
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39. Add data repository as the single
Point entry to your data
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40. Room
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41. A SQLite object mapping library
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43. Entities
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44. Data access object
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45. Application database
Building your database
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46. Be Together, Not the same
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47. Thank YOU